beam-interface

A beam.

The thickness property is the weight of beams, measured in staffspace. The direction property is not user-serviceable. Use the direction property of Stem instead.

User settable properties:

auto-knee-gap (dimension, in staff space)

If a gap is found between note heads where a horizontal beam fits that is larger than this number, make a kneed beam.

beamed-stem-shorten (list)

How much to shorten beamed stems, when their direction is forced. It is a list, since the value is different depending on the number flags/beams.

beaming (pair)

Pair of number lists. Each number list specifies which beams to make. 0 is the central beam, 1 is the next beam toward the note etc. This information is used to determine how to connect the beaming patterns from stem to stem inside a beam.

break-overshoot (pair of numbers)

How much does a broken spanner stick out of its bounds?

clip-edges (boolean)

Allow outward pointing beamlets at the edges of beams?

concaveness (number)

A beam is concave when its inner stems are closer to the beam than the two outside stems. This number is a measure of the closeness of the inner stems. It is used for damping the slope of the beam.

damping (number)

Amount of beam slope damping.

direction (direction)

If side-position is 1 (#X), then this property determines if the object is placed #LEFT, #CENTER or #RIGHT with respect to the other object. Otherwise, it determines if the object is placed #UP #CENTER or #DOWN. Numerical values may also be used. #UP=1, #DOWN=-1, #LEFT=-1, #RIGHT=1, CENTER=0 but also other numerical values are permitted.

gap (dimension, in staff space)

Size of a gap in a variable symbol.

gap-count (integer)

Number of gapped beams for tremolo.

grow-direction (direction)

Crescendo or decrescendo?

inspect-quants (pair of numbers)

If debugging is set, set beam/slur quant to this position, and print the respective scores.

knee (boolean)

Is this beam kneed?

length-fraction (number)

Multiplier for lengths. Used for determining ledger lines and stem lengths.

neutral-direction (direction)

Which direction to take in the center of the staff.

positions (pair)

Pair of staff coordinates (left . right), where both left and right are in the staff-space unit of the current staff.

thickness (number)

Line thickness, generally measured in line-thickness.

Internal properties:

details (list)

alist of parameters for detailed grob behavior.

more information on the allowed parameters can be found by inspecting lily/slur-scoring.cc, lily/beam-quanting.cc, and lily/tie-formatting-problem.cc. Setting debug-tie-scoring, debug-beam-scoring or debug-slur-scoring also provides useful clues.

least-squares-dy (number)

ideal beam slope, without damping.

quant-score (string)

Beam quanting score – can be stored for debugging

quantized-positions (pair of numbers)

Beam positions after quanting.

shorten (dimension, in staff space)

The amount of space that a stem. Internally used to distribute beam shortening over stems.

stems (unknown)

list of stem objects, corresponding to the notes that the arpeggio has to be before.

This grob interface is used in the following graphical objects: Beam